Redstone has sold parts of its legacy PBX business to Maintel Europe for £1.75m in cash.
Under ther terms of the deal, certain assets of Marcom Communications and other telephone systems maintenance contracts, which comprised a small part of Redstone Converged Solutions (RCS) business have been offloaded.
"We are pleased to have completed another step in our strategy of refocusing Redstone's operating activities and releasing cash from non-core activities," said Redstone chief executive Tony Weaver.
Only last month, Redstone closed its loss-making Building Schools for the Future division after novating its interest in contracts to construction firm Bovis Lend Lease.
The Marcom/ RCS businesses being sold had a combined turnover of £3m and an estimated EBITDA and assets of £300,000 in the year to 31 March 2010.
As part of the sale, 13 RCS and 27 Marcom employees have transferred to Maintel Europe in compliance with TUPE regulations. Maintel will continue to provide maintenance services for Redstone's Avaya customers.
Following the deal, Marcom will become a dormant company and the £1.75m will be used by the group to pay down borrowing.
"I look forward to updating shareholders furtther on our operational review and the implementation of our revised strategy when we publish our Half Year Report to 30 September," said Weaver.